private void MainCanvas_Drop(object sender, DragEventArgs e)
{
FrameworkElement elem = sender as FrameworkElement;
if (elem == null)
{
return;
}
IDataObject data = e.Data;
if (!data.GetDataPresent(typeof(FlowElement)))
{
return;
}
FlowElement source = data.GetData(typeof(FlowElement)) as FlowElement;
if (source == null)
{
return;
}
if (e.Source is FlowElement)
{
FlowLink FL = new FlowLink(source, (FlowElement)e.Source);
FL.LinkStyle = FlowLink.eLinkStyle.Arrow;
GEList.Add(FL);
SetFlowLinkConnectorsLocations(FL, e);
FL.Draw();
MainCanvas.Children.Add(FL);
}
}
private void SetFlowLinkConnectorsLocations(FlowLink FL, DragEventArgs e)
{
// We know the source connector the user clicked on
switch (mCurrnetFlowElemControl)
{
case "LeftConnector":
FL.SourcePosition = FlowLink.eFlowElementPosition.Left;
break;
case "RightConnector":
FL.SourcePosition = FlowLink.eFlowElementPosition.Right;
break;
case "TopConnector":
FL.SourcePosition = FlowLink.eFlowElementPosition.Top;
break;
case "BottomConnector":
FL.SourcePosition = FlowLink.eFlowElementPosition.bottom;
break;
}
// TODO: if we plan to enable more than the 4 basic connectors then make a list of connectors
//Destination - find closest connector to Mouse pos on the dest FlowElem
// We use the event args to get posiition since it is not reliable to use Mouse.GetPosition during drag operation
Point mp1 = e.GetPosition(FL.Destination.TopConnector);
double d1 = Point.Subtract(mp1, new Point(0, 0)).Length;
Point mp2 = e.GetPosition(FL.Destination.BottomConnector);
double d2 = Point.Subtract(mp2, new Point(0, 0)).Length;
Point mp3 = e.GetPosition(FL.Destination.LeftConnector);
double d3 = Point.Subtract(mp3, new Point(0, 0)).Length;
Point mp4 = e.GetPosition(FL.Destination.RightConnector);
double d4 = Point.Subtract(mp4, new Point(0, 0)).Length;
double min = d1;
FL.DestinationPosition = FlowLink.eFlowElementPosition.Top;
if (d2 < min)
{
min = d2;
FL.DestinationPosition = FlowLink.eFlowElementPosition.bottom;
}
if (d3 < min)
{
min = d3;
FL.DestinationPosition = FlowLink.eFlowElementPosition.Left;
}
if (d4 < min)
{
min = d4;
FL.DestinationPosition = FlowLink.eFlowElementPosition.Right;
}
}
public void AddConnector(FlowLink FL)
{
GEList.Add(FL);
FL.Draw();
MainCanvas.Children.Add(FL);
}